check out the FB Marketplace as well.
something else that occured, not to take away from the original posting- i had someone mail me a couple cards in a PWE.
I receieved the envelope but it was torn completely on the short side, from one end to the other as it was delivered in a sealed viewable Post Office mailer, with a tamper seal from the PO. Long story short- someone thought by the feel of it, that a gift card was inside, was tore open the envelope, then realized it was a football card and passed it through.
I know it cost it a little more, but may want to use some extra tape or a bubbler until the holidays are over.